A valve, in particular a suction valve (2), in particular in a high-pressure pump of a fuel injection system, has a valve element (14) that moves between an open position and a closed position, comprising a magnet armature (10) which is in mechanical contact with the valve element (14) in the axial direction and which is in contact with a first pressure spring (4) on the side facing away from the valve element (14), and wherein the magnet armature (10) can be axially moved via an electromagnetic actuation and same is supported in a starting position on a valve body (40) via a stop plate (20). The stop plate (20) is held in contact with the valve body (40) via a securing element (8).
|
1. A valve comprising a valve element (14) configured to move between an open position and a closed position, and a magnet armature (10), which is in mechanical contact with the valve element (14) in an axial direction and which is in contact with a first compression spring (4) on a side facing away from the valve element (14), and wherein the magnet armature (10) is configured to be moved axially by an electromagnetic actuation and, in a starting position, is supported on a valve body (40) via a stop plate (20), characterized in that the stop plate (20) is held in contact with the valve body (40) in the axial direction by a securing element (8), wherein the securing element (8) contacts the valve body (40) and the stop plate (20) and is radially inward from the valve body (40) and the stop plate (20).
21. A valve comprising a valve element (14) configured to move between an open position and a closed position, and a magnet armature (10), which is in mechanical contact with the valve element (14) in an axial direction and which is in contact with a first compression spring (4) on a side facing away from the valve element (14), and wherein the magnet armature (10) is configured to be moved axially by an electromagnetic actuation and, in a starting position, is supported on a valve body (40) via a stop plate (20), characterized in that the stop plate (20) is held in contact with the valve body (40) in the axial direction by a securing element (8), wherein the securing element is embodied as a fixing bush (8), which is embodied in a rotationally symmetrical way and is in contact all the way round with the inside diameter of the valve body (40) and the inside diameter of the stop plate (20).
2. The valve as claimed in
3. The valve as claimed in
4. The valve as claimed in
6. The valve as claimed in
7. The valve as claimed in
8. The valve as claimed in
9. The valve as claimed in
10. The valve as claimed in
12. The valve as claimed in
13. The valve as claimed in
14. The valve as claimed in
15. A method for producing a valve as claimed in
16. A high-pressure pump (1) of a fuel injection system having a suction valve (2) as claimed in
17. The valve as claimed in
18. The valve as claimed in
19. The valve as claimed in
20. The valve as claimed in
|
The invention relates to a valve, in particular a suction valve, in a high-pressure pump of a fuel injection system. The invention furthermore relates to a pump, in particular a high-pressure pump of a fuel injection system, in which the suction valve is used.
A valve, in particular an electromagnetically controllable suction valve, of a high-pressure pump of a fuel injection system is known from DE 10 2013 225 162 A1. The suction valve has a valve element that can move between an open and a closed position, having a magnet armature, which is in mechanical contact with the valve element in the axial direction and which is in contact with a first compression spring on the side facing away from the valve element, and wherein the magnet armature can be moved axially by an electromagnetic actuation and, in a starting position, is supported on a valve body via a stop plate.
The magnet armature is part of an electromagnetic actuator, which furthermore comprises a magnet coil. When the magnet coil is energized, a magnetic field is formed, thereby causing the magnet armature to move relative to the magnet coil against a spring force in order to close a working air gap.
The high-pressure pump known from DE 10 2013 225 162 A1 for a fuel injection system having a suction valve, in which all the elements described above are surrounded by fuel, has certain disadvantages.
Owing to the highly dynamic switching movements of the armature, there is the possibility, in the case of a stop plate which is capable of free axial movement in the valve body, of increased wear at the point of contact between the stop plate and the valve body. This is due to the fact that, particularly if the stop plate adheres to the magnet armature, the stop plate moves away from the valve body. During the return movement, there can be a collision between the stop plate and the valve body, wherein a high impelling force is exerted on the valve body and, during this process, the additional mass of the magnet armature, in particular, acts on the stop plate. This effect is intensified by the fact that the stop plate is composed of a harder material, and the relatively soft material of the valve body can be severely damaged as a result. As a result, there can be removal of material from the valve body in the region of contact and impairment of functioning or even a reduction in the life of the suction valve and thus of the high-pressure pump.
Moreover, the working air gap is enlarged by the wear and the loss of material on the valve body. This can lead to a restriction in the functioning of the suction valve or to a complete loss of functioning of the suction valve.
Adhesion of the stop plate to the magnet armature can furthermore lead to partial covering of the axial compensating holes in the magnet armature for an indefinite period of time. As a result, only limited flow of the surrounding fluid through the magnet armature is possible, with the result that there are unwanted fluctuations in the valve switching times. Furthermore, this effect of adhesion of the stop plate to the moving magnet armature is intensified in such a way that there can be increased adhesion of the stop plate to the magnet armature during an axial movement of the magnet armature in the direction of the valve body, owing to the direction of flow of the surrounding fluid. Adhesion and thus partial covering of the axial compensating holes in the magnet armature furthermore impairs the positive effects of the fluid flowing through, such as heat dissipation and/or removal of dirt from the suction valve.
The configuration according to the invention of the suction valve has the advantage that damage to a valve body by a stop plate making contact with an impelling force is prevented since the stop plate is held in contact with the valve body in the axial direction. On the one hand, this results in an extended life of the suction valve and thus of the entire high-pressure pump and, on the other hand, it results in a lower probability of failure of the suction valve. This is due to the fact that the formation of abrasive particles is reduced since damage to the valve body by the impinging stop plate is prevented.
Furthermore, the configuration of the suction valve in accordance with the invention has the advantage that avoidance and/or reduction of removal of material and damage to the valve body is achieved. As a result, enlargement of the working air gap over the life of the suction valve can be avoided, thereby making it possible to prevent restriction of the functioning of the suction valve or complete loss of functioning.
The configuration of the suction valve in accordance with the invention furthermore has the advantage that adhesion of the stop plate to the magnet armature is avoided. This makes it possible to prevent the occurrence of partial covering of axial compensating holes in the magnet armature. This has the advantage that unwanted fluctuating valve switching times, caused by restricted flow of the surrounding fluid through the magnet armature in both axial directions, depending on the axial direction of movement of the magnet armature, are prevented. Thus, the configuration of the suction valve in accordance with the invention ensures optimum removal of dirt from the suction valve and optimum cooling by the fluid flowing through.
According to the further features of the dependent claims, the inventive configuration of the valve or of the pump has further advantages over the prior art:
It is advantageous that a nonpositive and/or positive connection of a securing element to the valve element ensures that the stop plate is held reliably on the valve body in the axial direction for the life of the suction valve and thus of the high-pressure pump.
This reliable connection of the securing element to the valve element enables the stop plate and the valve body to be held in contact and thus ensures that an increase in the reliability and life of the suction valve is achieved.
Another advantage consists in that the securing element is connected positively and/or nonpositively to the stop plate. By this means, the stop plate can be held firmly on the valve body, and the stop plate can be prevented from moving axially away from the valve body. This, in turn, has the advantage that damage to the valve body is reduced and thus the probability of failure of the suction valve is reduced.
It is furthermore advantageous that a positive connection between the stop plate and the securing element is produced in such a way that machining of both parts in the course of production can be carried out with relatively little outlay since radial tolerance differences between the inside diameter of the stop plate and the outside diameter of the securing element can be compensated through elasticity of the securing element in the radial direction. By virtue of the beveling of the components comprising the stop plate and the securing element in the region of contact thereof and by virtue of the elasticity of the securing element, both components can furthermore also align themselves in the axial direction in such a way that contact between the stop plate component and the valve body is ensured in all cases. Even if there is a certain scatter in the outside and inside diameter tolerances during the production of the components, it is thus possible to ensure that the valve body and the stop plate are held reliably in contact. Cost savings during production are thereby possible.
A further advantage of the configuration according to the invention of the suction valve consists in that the use of the principle of latching makes it possible to achieve positive fixing of the securing element on the valve body and/or on the stop plate. In the case of the latching principle according to the invention, no further materials, such as adhesives or welding material, have to be used; instead, the positive connection can be achieved through the structural shaping of the components relative to one another. As a result, the assembly time can be shortened and costs can be saved by virtue of saved joining material and a shortened assembly time.
Moreover, the design configuration of the elements comprising the stop plate and the valve element requires only a low outlay on production since an encircling recess is formed uniformly and can be made in the respective component by means of a single production step. This leads to a cost saving and time saving in production.
The embodiment according to the invention of the securing element as an elastic element has a further advantage since in this way tolerance fluctuations in the axially relevant dimensions on the stop plate, on the valve body and also on the securing element, in particular in the tolerance chain of the elements, can be compensated. This reduces susceptibility to faults but also the production costs for the elements since an expanded tolerance range of the individual parts at the production level can be taken as a basis.
Furthermore, there is the advantage that the securing element is embodied as a one-piece solution. This reduces any susceptibility of the component to faults during assembly and in the assembled state since the vulnerability of a connection between a plurality of components is eliminated in the case of a one-piece solution. This reduces the susceptibility of the suction valve to failure.
The invention furthermore offers the advantage of simplified assembly by means of a first encircling recess in the valve body and by means of a second encircling recess in the stop plate since they can each form a positive connection with a first encircling raised portion and/or a second encircling raised portion of the securing element. Thus, the securing element has only to be inserted into the valve body and the stop plate and forms a stable joint by means of the latching principle. This reduces the effort involved in assembly and the costs which occur during assembly.
The configuration according to the invention of a fixing bush as an elastic element simplifies assembly since an improvement in the latching effect can be achieved.
By means of an optimized leading and trailing region of the raised portion, which can be embodied in such a way as to be straight, beveled or rounded, the fixing bush will slide almost automatically into the recess in the stop plate and in the valve element and can thus form a positive connection. The assembly forces can thus be reduced and a time saving and cost saving are obtained during assembly.
Further advantages of the method for producing the suction valve according to the invention:
By virtue of the fact that the securing element is first of all moved into a correct position relative to the stop plate and to the valve body and is then formed in such a way in a second step that a positive connection arises, the securing element can be produced while having to maintain less narrow tolerances. The final shaping to bring the securing element into a positive connection with the stop plate and the valve body can be accomplished by the method of forming. This results in a saving in production costs. Moreover, simplified assembly in just 2 steps is possible, this being obtained by insertion of the securing element and the subsequent forming. Here, advantages are obtained through a reduction in the assembly time and assembly costs.
An illustrative embodiment of the invention is shown in the drawing and explained in greater detail in the following description. In the drawing:
The high-pressure pump 1 has a pump casing 3 having a camshaft space 5. A camshaft 7 having a cam 9 designed, for example, as a double cam projects into the camshaft space 5. The camshaft 7 is mounted in two bearings, which are arranged on both sides of the cam 9 and are designed as radial bearings, these bearings being in the form of a casing bearing 11 arranged in the pump casing 3 and of a flange bearing 13, which is arranged in a flange 15 connected to the pump casing 3 and sealing off the camshaft space 5 in a leak tight manner with respect to the environment. The flange 15 has a through opening, through which a drive-side end portion 17 of the camshaft 7 projects. The drive-side end portion 17 has a taper, for example, on which a driving wheel is mounted and secured. The driving wheel is designed as a belt pulley or a gearwheel, for example. The driving wheel is driven directly or indirectly, e.g. via a belt drive or a gear mechanism, by the internal combustion engine.
Also inserted into the pump casing 3 there is a tappet guide 19, into which a roller tappet 23 having a running roller 21 is inserted. The running roller 21 runs on the cam 9 of the camshaft 7 during a rotary motion of the latter, and the roller tappet 23 is thus moved up and down in translation in the tappet guide 19. During this process, the roller tappet 23 interacts with a pump plunger 18, which is arranged in a cylinder bore 29, formed in a pump cylinder head 27, in such a way that it can likewise be moved up and down in translation.
Arranged in a tappet spring space 31 formed by the tappet guide 19 and the cylinder bore 29 is a tappet spring 33, which is supported at one end on the pump cylinder head 27 and at the other end on the roller tappet 23 and ensures continuous contact between the running roller 21 and the cam 9 in the direction of the camshaft 7. Formed in the pump cylinder head 27, as an extension of the pump plunger 18, is the pump working space 35, into which fuel is introduced via the electromagnetically controllable suction valve 2. The introduction of the fuel takes place during a downward movement of the pump plunger 18, while, during an upward movement of the pump plunger 18, fuel present in the pump working space 35 is pumped into the high-pressure reservoir via a high-pressure outlet 39 with an inserted outlet valve 16, via an onward-leading high-pressure line. Overall, the high-pressure pump 1 is fuel-lubricated, wherein the fuel is pumped from the low-pressure system into the camshaft space 5, which is connected in terms of flow to the suction valve 2. This electromagnetically controllable suction valve 2 and the functionality thereof are described below.
In the suction mode of the high-pressure pump 1, the electromagnetically controllable suction valve 2 is opened, and a connection between the pump working space 35 and a fuel inlet 26 is established, with the result that fuel is fed to the pump working space 35 via the suction valve 2. In the delivery mode of the high-pressure pump 1, the fuel fed to the pump working space 35 is compressed and is fed via the high-pressure valve 16 arranged in the high-pressure outlet 39 to a high-pressure reservoir (not shown). In the compression mode of the high-pressure pump 1, in which the pump plunger 18 moves upward, the suction valve 2 is closed when fuel delivery is supposed to take place, and it seals off the pump working space 35 from the fuel inlet 26.
The electromagnetically controllable suction valve 2 illustrated in
The valve element 14 is in contact with the magnet armature 10 via an armature stud 42, wherein the two elements are not connected to one another in the axial direction but are only held in contact with one another by magnetic forces and spring forces. The plunger-shaped valve element 14 is furthermore acted upon in the closing direction by the spring force of a second compression spring 12. The first compression spring 4 acts in the axial direction on the armature stud 42 and the magnet armature 10. In the deenergized state, the first compression spring 4 ensures that the armature stud 42 acts on the valve element 14 and holds it in an open position. Admittedly, this is counteracted by the second compression spring 12, but because the first compression spring 4 has a higher spring force the valve element 14 is held in an open state. Due to energization of the magnet armature 10 by means of the magnet coil 6, the magnet armature 10 moves away from the valve element 14, against the force of the first compression spring 4, in order to close the working air gap 28. Owing to the movement away, the armature stud 42 loses the nonpositive contact with the valve element 14, as a result of which the valve element 14 moves in the direction of the closed state owing to the force of the second compression spring 12. In the fully closed state of the valve element 14, it rests by means of the sealing surface 37 on the valve seat 36 and seals off the pump working space 35 from the fuel inlet 26.
Various illustrative embodiments of the combination of a securing element 8 with the stop plate 20 and the valve body 40 are explained below with reference to
The detail III illustrated in
A center line 45 is furthermore illustrated in
A center line 45 is furthermore illustrated in
Various embodiments are illustrated in
The above-explained illustrative embodiments and embodiments of the securing element 8 and/or of the fixing bush 8, of the stop plate 20 and of the valve body 40 can be combined with one another in any desired manner.
Patent | Priority | Assignee | Title |
Patent | Priority | Assignee | Title |
4678006, | Mar 24 1986 | LECTRON PRODUCTS, INC | Electrically operated automatic transmission controller assembly |
4690374, | Jan 09 1985 | Robert Bosch GmbH | Magnetic valve for fluid control |
4721254, | Dec 06 1984 | VDO Adolf Schindling AG | Electromagnetically actuatable fuel-injection valve |
4917351, | Mar 15 1989 | Micro-Flo Technologies, Inc. | Metering valve |
4947893, | Feb 28 1989 | Lectron Products, Inc. | Variable force solenoid pressure regulator for electronic transmission controller |
5393132, | Jun 29 1990 | Nippondenso Co., Ltd. | Brake control system and restriction adjusting valve for vehicles |
5513673, | May 23 1994 | LECTRON PRODUCTS, INC | Electrically modulated pressure regulator valve with variable force solenoid |
5626165, | Oct 17 1994 | Hadsys, Inc. | Valve for re-circulating exhaust gas |
5853028, | Apr 30 1997 | Eaton Corporation | Variable force solenoid operated valve assembly with dampener |
6439214, | Aug 14 2001 | SIEMENS AUTOMOTIVE INC | Linear solenoid automotive emission control valve |
6670875, | Feb 24 2000 | Delphi Technologies, Inc. | Magnetically-efficient solenoid for a linear actuator |
9771908, | Dec 23 2010 | Robert Bosch GmbH | Valve for injecting fuel |
20030042456, | |||
CN101089384, | |||
CN101680406, | |||
CN103180599, | |||
CN104583575, | |||
DE102013225162, | |||
DE102014214811, | |||
DE102014215589, | |||
DE3500449, |
Executed on | Assignor | Assignee | Conveyance | Frame | Reel | Doc |
Mar 01 2017 | Robert Bosch GmbH | (assignment on the face of the patent) | / | |||
Aug 20 2018 | KOLB, STEFAN | Robert Bosch GmbH | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 047477 | /0546 | |
Aug 24 2018 | HOLM, STEFFEN | Robert Bosch GmbH | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 047477 | /0546 |
Date | Maintenance Fee Events |
Oct 09 2018 | BIG: Entity status set to Undiscounted (note the period is included in the code). |
Date | Maintenance Schedule |
Jan 12 2024 | 4 years fee payment window open |
Jul 12 2024 | 6 months grace period start (w surcharge) |
Jan 12 2025 | patent expiry (for year 4) |
Jan 12 2027 | 2 years to revive unintentionally abandoned end. (for year 4) |
Jan 12 2028 | 8 years fee payment window open |
Jul 12 2028 | 6 months grace period start (w surcharge) |
Jan 12 2029 | patent expiry (for year 8) |
Jan 12 2031 | 2 years to revive unintentionally abandoned end. (for year 8) |
Jan 12 2032 | 12 years fee payment window open |
Jul 12 2032 | 6 months grace period start (w surcharge) |
Jan 12 2033 | patent expiry (for year 12) |
Jan 12 2035 | 2 years to revive unintentionally abandoned end. (for year 12) |